PHILADELPHIA (AP) — Officials say a Philadelphia man has died of carbon monoxide poisoning after being found unconscious in his home.

Fire officials say the unidentified man was found Tuesday morning by a woman who also lived at the North Philadelphia home. The woman was transported to a hospital for treatment of carbon monoxide poisoning.

Fire Commissioner Lloyd Ayers says the investigation is ongoing but officials suspect a broken and blocked flue pipe is responsible.

Ayers says the concentration of the odorless, colorless gas was more than eight times what is considered dangerous and would have been detectable by a carbon monoxide alarm. No such device was found in the home.

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